18 THE MARQUETTE IliON-BEAlil^^G DISTRICT. 



syenite, "quartz, compact and g-rannlar; imperfect talcose slates, which are 

 in some instances sliglitly argillaceous, and slaty hornblende " are the pre- 

 dominant t}-]Des. The rocks are more or less stratified, and are imperfectly 

 jointed. "Within the area of the metamoqihic rocks the surveyors saw 

 several knobs of syenitic granite and some dikes of greenstone. On the 

 sketch-map accompanying the report (opposite p. 880) are given the outlines 

 of the areas occupied by granite, metamorphic rocks, and clay-slates in 

 T. 48 N., R. 26 W.; T. 49 N., R. 25 W., and T. 47 N., R. 26 W. (See PI. I.) 



Hubbard, Bela. General observations upon the geology and toi)ograpby of 

 the district south of Lake Superior, subdivided in 1845 under direction of Douglass 

 Houghton, deputy surveyor. 33 st Congress, 1st session, 1849-50. Senate Docu- 

 ments, Vol. Ill, lS"o. 1, pages 833-842. 



Hubbard's report is upon the same district as is that of Burt, refeired 

 to above. The author divides the townships surveyed in 1845 into two 

 classes, in one of which he 2:)laces Ts. 46 X., 47 X., and 48 X., Rs. 24 W., 

 25 W., and 26 ^Y., all in the Marquette district. He then proceeds to 

 describe the geology of these towns. He adds little new to Burt's descrip- 

 tion, but his treatment of the subject is more satisfactory, as it is more 

 comprehensive. T. 46 X., Rs. 24 W., 25 "W., and 26 V\., and the lower 

 tier of sections in the towns north, are occupied by granites. These rocks 

 appear in a succession of rounded knobs, having' a general direction a little 

 south of west. They "vary much in character and composition, being 

 sometimes hoi-nblendic and approaching a perfect sienite, but more com- 

 monly feld.spatliic, or composed of quartz and feldspar.'' In the more 

 southerly portion of the district the feldspar is red, and the granite of a 

 coiTesponding tint. Soiue portions of the rock are massively stratified. 

 A second area of granite begins on the coast a little south of Presque Isle 

 and ii;ns westerly inland. It occupies the portion of T. 48 X., R. 25 W., 

 lying north of "Rio des Morts" (Dead River). "The granite of this 

 portion of the country is traversed by large and irregular dikes of green- 

 stone trap, and the granite itself puts on a trappean character, the two 

 rocks being sometimes with difficulty distinguished from each other. This 

 is the commencement of an apparently very large extent of granitic coun- 

 try extending westerly into the region not yet surveyed by section lines" 



